Officials from several countries vow to quickly determine who's behind Thursday's downing of Malaysia Airlines Flight MH-17 and the deaths of all 298 aboard.

U.S. intelligence officials confirmed that the crash was caused by a surface-to-air missile near Ukraine's border with Russia, but have yet to determine where it originated. The incident already is inflaming tensions between the two countries and escalating political rhetoric elsewhere.

It was "not an accident, it was blown out of the sky,'' said Vice President Joe Biden.

Malaysia Airlines said Ukrainian air traffic control lost contact with Flight MH17 about 30 miles from Russia. There were no distress calls as the Boeing 777, carrying 283 passengers and 15 crew, began to break apart as it fell from the sky in the world's deadliest aviation incident since 9/11.

Crash victims and body parts were strewn among burning debris up to 10 miles away. Among the dead: 154 Dutch nationals, 27 Australians, 11 Indonesians, six Brits, four Germans, four Belgians, four French, three Filipinos and a Canadian. Malaysian Air officials have so far not identified any Americans among the passengers, although they cautioned that some nationalities have still not been verified.

The White House said late Thursday night that "We continue to seek information to determine whether there were any American citizens on board."

The crash site is in Ukraine's war-torn Donetsk region, where political unrest and scattered fighting between Ukraine and pro-Russian militants has festered for months. After the downing of several Ukraine aircraft in recent days, accusations, blame and finger-pointing over Thursday's crash was fevered.

Ukrainian President Petro Poroshenko called the crash "an act of terrorism' and demanded an international investigation. Ukrainian officials said they had intercepted telephone calls of a separatist leader discussing the crash with Russian military intelligence officers. Separatists initially believed they had downed a military cargo plane, according to the SBU, Ukraine's main security agency.

Buy Photo

(Photo: Sergei Supinsky, AFP/Getty Images)

But Russian President Putin blamed the incident on Ukraine's government, which "carries responsibility for this horrible tragedy."

"We will do everything – everything that depends on us, in any case – to ensure that an objective picture of the events becomes accessible for our public and for the Ukrainian public and the entire world," Putin said.

In brief remarks at an appearance in Wilmington, Del., President Obama called the incident a "terrible tragedy" and said the U.S. will offer "any services it can" to determine what happened.

Armed separatists in military attire block passage of Organization for Security and Co-operation in Europe investigators heading to the wreckage site of Malaysia Airlines Flight 17.
Evert-Jan Daniels, European Pressphoto Agency

Sympathizers hug in front of a flower tribute at the entrance to the Korporaal van Oudheusdenkazerne army barracks in Hilversum, Netherlands, on July 24. Victims of the Malaysia Airlines Flight 17 crash in the Ukraine will be identified at the facility.
Jerry Lampen, epa

The convoy of funeral hearses carrying the remains of the Malaysia Airlines Flight 17 crash victims heads July 24 from the airbase in Eindhoven to Hilversum, Netherlands, where they will be identified.
Remko De Waal, EPA

People attend a silent march of remembrance in Amsterdam on July 23. The first bodies of passengers and crew killed on Malaysia Airlines Flight 17 arrived in the Netherlands from the Ukraine. July 23 was an official day of mourning in the Netherlands.
Phil Nijhuis, AP

Hearses carry coffins containing unidentified bodies from the crash of Malaysia Airlines Flight 17 on July 23, in Eindhoven, Netherlands. The flight was traveling from Amsterdam to Kuala Lumpur when it crashed in eastern Ukraine killing all 298 passengers.
Peter Macdiarmid, Getty Images

Mourners watch from a bridge as a convoy of hearses carrying some victims of the downed Malaysia Airlines Flight 17, drive from Eindhoven Airbase to Hilversum, Netherlands.
Jerry Lampen, AFP/Getty Images

Dutch military men carry a coffin containing the body of a victim of downed Malaysia Airlines Flight 17, during a ceremony at Eindhoven Airbase upon their arrival in Netherlands.
John Thys, AFP/Getty Images

A woman mourns victims of Malaysia Airlines Flight 17 at Amsterdam's Schiphol Airport on July 23. The Dutch government has declared a day of national mourning as two planes arrive, carrying victims from the flight that crashed in Ukraine.
Robin Van Lonkhuijsen, AFP/Getty Images

Malaysian experts check debris at the Malaysia Airlines crash site on July 22 near Hrabove, Ukraine. The aircraft was traveling from Amsterdam to Kuala Lumpur when it was shot down by a missile on July 17, killing all 298 people on board.
Robert Ghement, epa

A Malaysian investigator photographs debris at the scene of the Malaysia Airlines jet crash near Hrabove, Ukraine. The Boeing 777 aircraft with 298 people onboard was shot down by a missile July 17.
Vadim Ghirda, AP

Pro-Russian rebels, right, followed by members of the OSCE mission, walk by plane wreckage as they arrive for a media briefing at the crash site of Malaysia Airlines Flight 17, near the village of Hrabove, in eastern Ukraine, on July 22.
Vadim Ghirda, AP

Deputy head of a European observer mission to Ukraine Alexander Hug, center right, stands outside a refrigerated train as members of Netherlands' National Forensic Investigations Team inspect the bodies of victims from the Malaysia Airlines crash in Torez, eastern Ukraine.
Vadim Ghirda, AP

Kees Klompenhouwer, the Dutch ambassador to Ukraine, left, and Ukrainian President Petro Poroshenko lay flowers to commemorate the victims of the crash at the Dutch Embassy in Kiev.
Sergey Dolzhenko, European Pressphoto Agency

Luggage and personal belongings from Malaysia Airlines Flight 17 lie in a field on July 20 near Grabovo, Ukraine. The airliner was traveling from Amsterdam to Kuala Lumpur when it crashed, killing all 298 on board, including 80 children.
Rob Stothard, Getty Images

A pro-Russia soldier holds up a toy he found in the debris at the Malaysia Airlines crash. Emergency workers, police officers and off-duty coal miners searched the scene of the crash for the bodies of 298 people who died in the July 17 crash.
Dmitry Lovetsky, AP

Alexander Hug, center, deputy chief monitor of the Organization for Cooperation and Security in Europe's special monitoring mission to Ukraine, visits the site of the airliner crash near Shaktarsk.
Dominique Faget, AFP/Getty Images

Interpreters work as Ukrainian Ambassador to the United Nations Yuriy Sergeyev speaks at a Security Council meeting at the United Nations headquarters in New York.
Andrew Gombert, European Pressphoto Agency

Pro-Russia militants stand next to wreckage from Malaysia Airlines Flight 17 near Donetsk. The Boeing 777 airliner with 298 people on board was possibly shot down by a missile on July 17 near the Russia-Ukraine border.
Anastasia Vlasova, European Pressphoto Agency

A man covers a body with a plastic sheet near the Malaysia Airlines crash site near Rozsypne village, Ukraine. Rescue workers, police officers and off-duty coal miners are searching for victims in an area in eastern Ukraine where the Malaysian plane was shot down on July 17, killing all 298 passengers.
Dmitry Lovetsky, AP

People inspect the debris after a Malaysia Airlines passenger jet with 295 people on board crashed near Grabovo. Ukrainian military officials say the Boeing 777 passenger plane carrying 295 people was shot down by a missile as it flew over rebel-held eastern Ukraine.
Dmitry Lovetsky, AP

Relatives of passengers aboard the shot down Malaysian airliner walk past members of the press as they arrive at Schiphol airport in Amsterdam. The flight was carrying 295 people from Amsterdam to Kuala Lumpur.
Phil Nijhuis, AP

People inspect the crash site of a passenger plane near the village of Grabovo. Both the government and the pro-Russia separatists fighting in the region denied any responsibility for downing the plane.
Dmitry Lovetsky, AP

Said Malaysian Prime Minister Najib Razak; "We must and we will find out precisely what happened to this flight. No stone will be left unturned."

The crash occurred two hours after the flight departed Amsterdam at about 12:15 p.m. local time. It's the second disaster involving a Malaysia Air Boeing 777 this year. On March 8, Flight 370 disappeared with 239 passengers and crew aboard on a flight from Kuala Lumpur to Bejiing. Despite one of the most extensive searches in flight history, Flight 370 has yet to be found.

Anton Gerashenko, an adviser to Ukraine's Interior Ministry, said on Facebook that Flight MH17 was hit by a BUK anti-aircraft missile. Usually vehicle-mounted, the BUK can simultaneously track and strike multiple targets at different directions and altitudes, according to military think tank Globalsecurity.org.

A separatist leader in Donetsk denied that rebel forces had the capability to bring down a high-flying aircraft. Alexander Boroday, chairman of the Council of Ministers of the self-proclaimed Republic of Donetsk, called the incident a provocation by the Ukrainian military, Russia's Interfax news agency reported.

"Self-defense forces have no air-defense, which could target transport aircraft at that height," he told Interfax.

On Wednesday, a Russian military plane allegedly shot down a Ukrainian Su-25 jet fighter over Ukrainian territory, forcing the pilot to eject. Pro-Russian rebels claimed responsibility for hitting a second Su-25 with a portable surface-to-air missile. The pilot managed to land the plane safely.

"There have been Ukrainian helicopters and aircraft operating under the assumption of limited separatist capabilities,'' said Damon Wilson, a Russia and Ukraine expert in the administrations of George W. Bush and Bill Clinton. "They've learned quite rudely that the separatists have more advanced weapons."

Separatists have used a version of Russia's Grad rocket that Russian military only began using in January, Wilson said, citing sources in "U.S. government circles."

"This is not older, former equipment but among the most recent Russian equipment used in the Russian military," said Wilson, now deputy executive vice president at the Atlantic Council, a Washington think tank.

German, British and French airlines say they are keeping flights from crossing the region.

In Kuala Lumpur, several relatives of those aboard the jet came to the international airport.

A distraught Akmar Mohamad Noor, 67, said her older sister was coming to visit the family for the first time in five years. "She called me just before she boarded the plane and said 'see you soon,'" Akmar said.

Several passengers were heading to an international AIDS conference in Australia.

Australian Foreign Affairs Minister Julie Bishop said Friday that several people on board the Boeing 777 were en route to Melbourne to attend next week's conference.

The International AIDS Society issued a statement expressing "sincere sadness" that several of its colleagues and friends were on board the plane.

Bishop says at least 27 Australians were on board. The aircraft was scheduled to continue flying to the western Australian city of Perth after stopping in Kuala Lumpur.

MH17 was shot down by a missile July 17 over eastern Ukraine en route from Amsterdam to Kuala Lumpur, Malaysia. Under mounting world pressure, pro-Russian rebels have handed over data-filled "black boxes" from the downed Boeing 777 to Malaysian officials.